Ni3N@C nanocomposite was prepared by a simple one-step low-temperature pyrolysis method with nickelacetate in flowing ammonia. The spherical Ni3N nanoparticles were uniformly coated with a carbon protective layerformed in-situ with a thickness of 10 nm, which shows excellent catalytic activity for overall water splitting in alkalinesolution. The experimental results showed that the initial potential for hydrogen evolution reaction (HER) was 0.06 V(versus reversible hydrogen electrode, vs RHE), and the overpotential () was 284mV at the current density of 10mAcm2; the initial potential for oxygen evolution reaction (OER) was 1.53 V vs RHE, and was 390 mV at the currentdensity of 10 mA cm2. In addition, Ni3N@C had excellent stability for overall water splitting in alkaline solution. Theexcellent activity and high stability of the catalyst are due to the high intrinsic activity of Ni3N as well as the formationof carbon coating layer, which not only improves the conductivity of the material and accelerates the transfer of electronsand protons, but also protects Ni3N from corrosion in alkaline electrolyte. In a word, we provide a simple, economicaland low-temperature sustaining method to prepare Ni3N to be used in water splitting, and the preparationmethod can also be used to prepare other promising bifunctional electrocatalysts for energy conversion field.